Others have given feedback I would give on the controls and difficulty, so I'll just say that the level of polish here is amazing! The squash-and-stretch when you jump, the effects when you grind (or explode), the nice little sound effects — gave me a huge nostalgic throwback to playing web games in school. Neat stuff!
Edit: Ah, had to come back and try for the high score. Got 2144 and then I wasn't fast enough on a jump. Enjoying the top spot (for now — I'm sure someone will take it from me)!